A 25-year-old man has bronchospasm that is exercise induced, paicularly in the cold weather. He takes his medication 15 minutes prior to anticipated exercise, which will help to prevent the asthmatic attack but does not produce bronchodilation. Which drug does he take?
**Core Concept**
The patient has exercise-induced bronchospasm (EIB), a condition where the airways constrict in response to physical exertion, particularly in cold weather. This condition is often associated with asthma. The medication taken by the patient is a type of bronchodilator, but it works differently from the typical bronchodilators used for acute asthma attacks.
**Why the Correct Answer is Right**
The patient takes a medication that helps to prevent the asthmatic attack by inhibiting the release of mediators involved in the allergic response. This medication is a mast cell stabilizer, which works by inhibiting the enzyme phosphodiesterase (PDE) 4, thereby reducing the release of histamine and other mediators from mast cells. This action prevents the airway constriction associated with EIB. The medication does not produce immediate bronchodilation, which is why it is taken before exercise to prevent the asthmatic attack.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because beta-2 agonists (e.g., albuterol) are typical bronchodilators used for acute asthma attacks and would not prevent the asthmatic attack in this scenario.
**Option B:** This option is incorrect because anticholinergics (e.g., ipratropium) are used to relax smooth muscle in the airways and would provide immediate bronchodilation, which is not the mechanism of action in this scenario.
**Option C:** This option is incorrect because corticosteroids (e.g., prednisone) are used to reduce inflammation in the airways and would not provide immediate relief for EIB.
**Clinical Pearl / High-Yield Fact**
Mast cell stabilizers, such as cromolyn sodium, are often used to prevent EIB by inhibiting the release of mediators involved in the allergic response. They are particularly useful for patients who experience EIB, as they can help to prevent the asthmatic attack without providing immediate bronchodilation.
**Correct Answer:** C. Cromolyn sodium.